Calcium bromide, while resembling them in its action, is less energetic than the other bromides.

Zinc bromide is the most irritant, and is supposed to possess both tonic and sedative properties.

Strontium bromide is the mildest of all, being less prone to cause bromism. Its action is slow.

Diluted hydrobromic acid in its action resembles the bromides, though much less depressant than the potassium salt, and less likely to occasion symptoms of chronic poisoning. As an acid it is a gastric irritant.

Therapeutics. - Externally and Locally. - Pharyngitis is relieved by a gargle containing potassium bromide and potassium chlorate. A solution of potassium bromide diminishes the sensibility of the throat, so that examinations are more easily made. A solution of 4 parts of potassium bromide in 20 parts of glycerin affords a soothing lotion in painful hemorrhoids.

Internally. - The bromides are especially useful in allaying excessive brain activity, the insomnia (particularly the sleeplessness dependent upon nervous excitement, exhaustion, and irritability) and headache of cerebral congestion, yielding readily to these remedies.

They are considered to be very efficient medicinal agents for the relief of epilepsy, being given either alone or in combination with some vegetable bitter. Fere combines with them an intestinal antiseptic, asserting that the union lessens the tendency of bromism. Recent studies of Nencki on the power of potassium bromides to replace, in part, sodium chloride in the tissues suggested the idea of withdrawal of all salt from the epileptic's dietary and to replace it with small quantities of bromide. This permits of complete bromi-zation with smaller quantities and is a distinctly useful procedure.

Being such marked depressants of the reflex centers, they are of decided benefit in nervous spasmodic disorders, and particularly valuable in infantile convulsions.

During dentition children suffer from various disturbances due to irritation of the dental nerve - convulsions, cough, indigestion, diarrhea, strabismus, etc. - in all of which the bromides, being powerful depressants of the reflex mechanism, prove of great value.

Whenever there is increased reflex excitability the bromides are indicated. They are therefore valuable in the reflex disturbances of the menopause, spasmodic asthma, laryngismus stridulus, whooping cough, and other coughs of reflex origin. They have also been used in tetanus and strychnine-poisoning.

Excessive nervous irritability is quickly relieved by these remedies, either singly or in combination with some of the antispasmodics, such as asafetida, valerian, etc.

Because they depress the sexual mechanism they are of decided benefit in spermatorrhea of the plethoric or in the condition arising from irritation of the deep urethra. Menorrhagia resulting from excessive ovarian excitement is frequently relieved by these agents, while nymphomania and delirium tremens are often greatly benefited by full doses of the bromides.

The ammonium bromide has been employed with benefit, it is said, in diabetes of nervous origin. Cerebral vomiting and the vomiting of pregnancy are sometimes singularly amenable to the influence of the bromides.

A combination of sodium bromide, spirit of nitrous ether, and tincture of aconite, in anise water, as a remedy in acute febrile attacks of children with delirium is of distinct value. Small doses are given at frequent intervals until there is a decided improvement in the symptoms.

The sedative action upon the circulatory apparatus exerted by potassium bromides renders it valuable in cardiac irritability when not due to anemia. It is particularly useful in quieting the heart's action in exophthalmic goiter.

The bromides are distinctly valuable in combination with chloral to relieve chordee and to diminish the tendency to sexual excitement which is antecedent to this condition. In irritative cystitis the bromides are also of service.

Bromides are useful in the convulsive respiratory disorders, and are also helpful in seasickness.

Diluted hydrobromic acid is used for the same purposes as the bromides, some clinicians preferring it to the latter to quiet the delirium of simple continued fevers. It is employed extensively to relieve the symptoms of cinchonism.

Bromoform is useful as an antispasmodic in whooping cough, but it should be carefully administered, as dangerous collapse, as in chloroform poisoning, has been frequently reported.

Contraindications. - The bromides are contraindicated in conditions of great debility, anemia, or fatty or weak heart with low arterial pressure.

Administration. - The bromides should be given in solution, and when long continued, as in the treatment of epilepsy, they should be accompanied by restorative agents. Carbonated waters, milk, and aromatic elixir serve as efficient vehicles to disguise the taste of these salts.

Children acquire a remarkable tolerance for the bromides, so that large doses may be given them with little danger.

Bromoform may be dropped into a spoonful of water and administered in this simple manner, or it may be dissolved in glycerin.

The diluted hydrobromic acid should be given in water or syrup.